Abstract:

It has been recognized since the 1950's that radioisotopic
disequilibrium between naturally occurring parent-daughter
isotope pairs in seawater can provide information
on the rate of processes segregating them. In the surface
ocean, the U-238:Th-234 parent-daughter pair tends to display
measurable disequilibrium that is attributable to the
effects of scavenging on particle reactive thorium. A range
of approaches has been applied to deriving quantitative information
on particle scavenging and sinking rates from U-238:Th-234 measurements. Here, we review the mathematical
underpinnings of a very basic conceptual model of the
removal process in order to correct a misunderstanding that
has arisen in recent literature.